Lecture 344/24/06. Entropy (Measurement of disorder) Related to number of microstates ∆S universe = ∆S system + ∆S surroundings 2 nd Law of Thermodynamics.

Slides:



Advertisements
Similar presentations
Department of Chemistry and Biochemistry CHM Reeves CHM 101 – Chapter Nineteen Spontaneous Processes Entropy & the Second Law of Thermodynamics The.
Advertisements

Lecture 354/29/05 TSC 006 Tuesday, May 3 from 2:30 - 3:30 p.m.
Lecture 314/10/06. Thermodynamics: study of energy and transformations Energy Kinetic energy Potential Energy.
Chapter 19 Chemical Thermodynamics
Lecture 314/20/07. Section 1 Equilibrium Le Chatelier’s Solubility Section 2 Acid/Base equilibria pH Buffers Titration Section 3 Oxidation numbers Balancing.
The entropy, S, of a system quantifies the degree of disorder or randomness in the system; larger the number of arrangements available to the system, larger.
Lecture 334/21/06. QUIZ 1.A 12.3 g sample of iron requires heat transfer of 41.0 J to raise its temperature from 17.3 ºC to 24.7 ºC. Calculate the specific.
Copyright 1999, PRENTICE HALLChapter 191 Chemical Thermodynamics Chapter 19 David P. White University of North Carolina, Wilmington.
System. surroundings. universe.
Thermodynamics Chapter 19 Liquid benzene Production of quicklime Solid benzene ⇅ CaCO 3 (s) ⇌ CaO + CO 2.
Lecture 334/25/05. 1 st Law of Thermodynamics revisited ∆E = q + w Change in Energy content heat work.
Lecture 304/18/07. Solid/Liquid Heat of fusion Solid  Liquid Endothermic ice  Water (333 J/g or 6 KJ/mol) Heat of crystallization Liquid  Solid Exothermic.
Chemical Thermodynamics © 2009, Prentice-Hall, Inc. Chapter 19 Chemical Thermodynamics Chemistry, The Central Science, 11th edition Theodore L. Brown;
Chapter 19 Chemical Thermodynamics
Entropy and the 2nd Law of Thermodynamics
Chemical Thermodynamics BLB 12 th Chapter 19. Chemical Reactions 1. Will the reaction occur, i.e. is it spontaneous? Ch. 5, How fast will the reaction.
CHEM 163 Chapter 20 Spring minute exercise Is each of the following a spontaneous change? Water evaporates from a puddle A small amount of sugar.
Chemical Thermodynamics. Spontaneous Processes First Law of Thermodynamics Energy is Conserved – ΔE = q + w Need value other than ΔE to determine if a.
Thermodynamics Chapter st Law of Thermodynamics Energy is conserved.  E = q + w.
Chapter 19 Chemical Thermodynamics Lecture Presentation John D. Bookstaver St. Charles Community College Cottleville, MO © 2012 Pearson Education, Inc.
CHEMICAL THERMODYNAMICS The Second Law of Thermodynamics: The is an inherent direction in which any system not at equilibrium moves Processes that are.
Chapter 19 Chemical Thermodynamics John D. Bookstaver St. Charles Community College St. Peters, MO 2006, Prentice Hall, Inc. Modified by S.A. Green, 2006.
Spontaneity, Entropy, and Free Energy
Spontaneity, Entropy, & Free Energy Chapter 16. 1st Law of Thermodynamics The first law of thermodynamics is a statement of the law of conservation of.
Ch. 19: Chemical Thermodynamics (Thermochemistry II) Chemical thermodynamics is concerned with energy relationships in chemical reactions. - We consider.
First Law of Thermodynamics-The total amount of energy in the universe is constant. Second Law of Thermodynamics- All real processes occur spontaneously.
Chapter 19 Chemical Thermodynamics. First Law of Thermodynamics Energy cannot be created nor destroyed. Therefore, the total energy of the universe is.
Thermodynamics Chapter 18.
Chapter 20: Thermodynamics
First Law of Thermodynamics  You will recall from Chapter 5 that energy cannot be created nor destroyed.  Therefore, the total energy of the universe.
Prentice Hall © 2003Chapter 19 Chapter 19 Chemical Thermodynamics CHEMISTRY The Central Science 9th Edition David P. White.
In general, the more atoms in its molecules, the greater is the entropy of a substance Entropy is a function of temperature.
Chapter 17 Free Energy and Thermodynamics Lesson 1.
THERMODYNAMICS!!!! Nick Fox Dan Voicu.
A.P. Chemistry Spontaneity, Entropy, and Free Energy.
Thermodynamics 3. 2 nd Law of Thermodynamics The driving force for a spontaneous process is an increase in the entropy of the universe. Entropy, S, can.
Thermodynamics Follow-up Kinetics The reaction pathway Thermodynamics the initial and final states.
Chemical Thermodynamics © 2009, Prentice-Hall, Inc. Topic 9 Chapter 18 Chemical Thermodynamics.
Thermodynamics Mr. Leavings. Objectives Use the laws of thermodynamics to solve problems, identify energy flow within a system, determine the classification.
Chapter 19: Chemical Thermodynamics
Chapter 19 Chemical Thermodynamics Lecture Presentation John D. Bookstaver St. Charles Community College Cottleville, MO © 2012 Pearson Education, Inc.
Prentice Hall © 2003Chapter 19 Chapter 19 Chemical Thermodynamics CHEMISTRY The Central Science 9th Edition.
AP Chapter 19.  Energy can not be created nor destroyed, only transferred between a system and the surroundings.  The energy in the universe is constant.
Entropy. Spontaneous Processes Spontaneous processes are those that can proceed without any outside intervention. The gas in vessel B will spontaneously.
Section 19.1 Entropy and the Three Laws of Thermodynamics
Spontaneity. Spontaneous Processes P/C change that occurs with no outside intervention exothermic chemical rxns are spontaneous energy still must be supplied.
CHE 116 No. 1 Chapter Nineteen Copyright © Tyna L. Meeks All Rights Reserved.
Chemical Thermodynamics. Recall that, at constant pressure, the enthalpy change equals the heat transferred between the system and its surroundings. 
Is this your room? Then you already know about entropy.
Entropy – Randomness & Disorder Mr Nelson
Chemical Thermodynamics BLB 11 th Chapter 19. Chemical Reactions 1. How fast will the reaction occur? Ch How far toward completion will the reaction.
Chemistry 101 : Chap. 19 Chemical Thermodynamics (1) Spontaneous Processes (2) Entropy and The Second Law of Thermodynamics (3) Molecular Interpretation.
Chemical Thermodynamics © 2009, Prentice-Hall, Inc. Chapter 19 Chemical Thermodynamics Chemistry, The Central Science, 11th edition Theodore L. Brown;
Prentice Hall © 2003Chapter 19 Chapter 19 Chemical Thermodynamics CHEMISTRY The Central Science 9th Edition David P. White.
Entropy (S) is a measure of the randomness or disorder of a system. orderS disorder S  S = S f - S i If the change from initial to final results in an.
Chemical Thermodynamics  2009, Prentice-Hall, Inc. First Law of Thermodynamics You will recall that energy cannot be created nor destroyed. Therefore,
Chapter 19: Thermodynamics First Law of Thermodynamics: energy cannot be created or destroyed -total energy of the universe cannot change -you can transfer.
Chemical Thermodynamics First Law of Thermodynamics You will recall from earlier this year that energy cannot be created nor destroyed. Therefore, the.
Advanced Thermochemistry Mrs. Stoops Chemistry. Chapter Problems Ch 19 p742: 16, 20, 28, 34, 38, 40, 46, 52, 56, 58, 75, 93.
AP Chemistry Chapter 5 and 19 Jeopardy Jennie L. Borders.
Chapter 17 Free Energy and Thermodynamics 2008, Prentice Hall Chemistry: A Molecular Approach, 1 st Ed. Nivaldo Tro Roy Kennedy Massachusetts Bay Community.
Chapter 19 Spontaneity, entropy and free energy (rev. 11/09/08)
Thermodynamics Chander Gupta and Matt Hagopian. Introduction into Thermo Thermodynamics is the study of energy and its transformations Thermochemistry.
Chemical Thermodynamics Chapter 19 Chemical Thermodynamics 19.1 Spontaneous Processes 19.2 Entropy and the Second Law of Thermodynamics 19.3 The Molecular.
Chapter 19 Chemical Thermodynamics
Entropy and Gibbs Free Energy
Chemical Thermodynamics Lecture 1. Chemical Thermodynamics.
Presentation transcript:

Lecture 344/24/06

Entropy (Measurement of disorder) Related to number of microstates ∆S universe = ∆S system + ∆S surroundings 2 nd Law of Thermodynamics Entropy of the universe increases with spontaneous reactions Reversible reactions vs. Irreversible reaction

3 rd Law of thermodynamics S = O at O K S° - entropy gained by converting it from a perfect crystal at 0 K to standard state conditions

Degrees of freedom translational motion molecules in gas > liquid > solid vibrational motion movement of a atom inside a molecule rotational motion rotation of a molecule

Entropy trends Entropy increases: with more complex molecules with dissolution of pure gases/liquids/solids with increasing temperature with increasing volume with increasing # moles of gases

Which has higher entropy? dry ice orCO 2 liquid water at 25°Corliquid water at 50°C pure Al 2 O 3 (s)orAl 2 O 3 with some Al 2+ replaced with Cr 3+ 1 mole of N 2 at 1 atmor1 mol of N 2 at 10 atm CH 3 CH 2 CH 2 CH 3 (g)or CH 3 CH 3 (g)

Is the reaction spontaneous?

Gibbs Free Energy ( ∆G) ∆G° = ∆H° - T∆S° ∆G = ∆H - T∆S ∆G° = Σn∆G f ° (products) - Σn∆G f ° (reactants)

Gibbs Free Energy ∆G = ∆H - T∆S ∆H∆S-T∆S∆G spontaneous? example -+ 2O 3 (g)  3O 2 (g) +- 3O 2 (g)  2O 3 (g) -- H 2 O (l)  H 2 O (s) ++ H 2 O (s)  H 2 O (l)

Gibbs Free Energy (∆G) and equilibrium R = J/mol-K

Example A hot plate is used to heat two 50-mL beakers at the same constant rate. One beaker contains 20.0 grams of graphite (C=0.79 J/g-K) and one contains 10 grams of ethanol (2.46 J/g-K). Which has a higher temperature after 3 minutes of heating?